ChangingCottonLandscapeNeilForrester

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96.1%, respectively). High levels of parasitism (up to 70%) were also reported by entomologists in the Sindh late season in 2008. Dr. Chamberlain followed up these late 2008 season collections with further collections from the lower Punjab in the following season (mid and late season mealybug collections at two sites and from another two sites where mealybugs appeared only late in the season). Once again very high levels of parasitism were recorded (88- 94%) in late season populations where the parasites had time to establish with lower levels (30- 35%) where infestations were only recent (see Dr. Chamberlain’s data in the Table below). 2008 Oct 2009 Date 9th July 12th Sept Location Number of mealybugs sampled 9 12 15 18 21 24 Total Lodhran 86 - 8 12 31 30 - 81 94.2 Rahim Yar Khan 103 - 10 28 40 21 - 99 96.1 Iqbal Bagh 76 - 6 12 18 9 - 45 59.2 Rang Pur 97 - 9 19 24 7 - 59 60.8 Iqbal Bagh 84 - 13 23 29 14 - 79 94.0 Rang Pur 65 - 9 19 17 12 - 57 87.7 Kot Sardar Khan 102 - 5 15 7 4 - 31 30.4 Roti Shareef 75 - 4 7 10 5 - 26 34.7 Data source: Kindly supplied by Dr. David Chamberlain (pers. comm.) Number of parasites emerging (days after collection) 14 % parasitism Dr Chamberlain’s observations on the abundance of the encyrtid parasite Aenasius sp. certainly fit with field observations of declining mealybug infestations starting in 2008 with a continuing decline into 2009. Given continuing high levels of parasitism, one should be confident to anticipate that the mealybug populations will be reduced to very low levels and assuming that they are not triggered off again, should now be able to held in check by their natural enemies. In this regard, the current introduction of the mealybug destroying ladybird Cryptolaemus montrouzieri by CABI can only help in assisting to keep the mealybug populations in check.
What is the long term solution to the mealybug menace? Pakistan entomologists need to do some basic research on the ecology of the mealybug and its natural enemies to determine what the trigger for the mealybug population explosion was in 2005-2007. If and when this trigger is identified and it can be attributed to be caused by human activities, then all management efforts should be made to ensure that this trigger is never again activated. 2.3 Lack of a professional seed industry Pakistani cotton growers have been plagued with this problem for many years. The result is that the planting seed they have been supplied with often has poor germination and is mostly lacking in genetic purity because of breeding shortcuts, haste to market and seed contamination, often at the gin. Growers often end up trying to manage a mixture of varieties in the one field so that any one crop management decision may not necessarily be the best one for all the varieties in the field. For example in the picture below, there is a pure seed production block in the background, rogued for off types. In the foreground, is a commercial field of the same variety with clearly a range of different types and maturities in the same field, including even desi cotton (Gossypium arboreum) off types. Pure seed production block Same variety, commercial seed, separated by road Desi cotton contaminants This has been an on-going problem for the conventional seed market and will become even more important for the developing transgenic cotton seed market. Quality assurance is critical 15
Page 1: Changing the Cotton Landscape in Pa
Page 5: Preface The importance of improving
Page 8 and 9: Acronyms AARI Ayub Agricultural Res
Page 10 and 11: Millions of Bales (170 kgs) Yield (
Page 12 and 13: Millions of bales (170 kgs) 35.0 30
Page 14 and 15: 4.1b/year in extra lint, oil and me
Page 16 and 17: CLCV susceptible variety in the Ind
Page 18 and 19: (Feb/March) of part of their cotton
Page 20 and 21: The following table presents data o
Page 24 and 25: for transgenic seed production othe
Page 26 and 27: 2) Ensure all private seed sector c
Page 28 and 29: Logistical problems It will be very
Page 30 and 31: the introduction of Roundup Ready F
Page 32 and 33: eview and will not be discussed fur
Page 34 and 35: Following is a list of insect toler
Page 36 and 37: The key factors affecting the devel
Page 38 and 39: • Disease tolerance, especially F
Page 40 and 41: whatever natural refuges are availa
Page 42 and 43: The models above clearly indicate t
Page 44 and 45: 7. Summary of Recommendations 1) En
Page 46 and 47: case, we need to carefully examine
Page 48 and 49: Stakeholders Engaged for this Study

ChangingCottonLandscapeNeilForrester

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